DARPA Experts on Why We Should Be Optimistic About the Search for Alien Life

Today is the last day of DARPA's Wait... What? conference, a forum for thinkers about futuristic technologies, so naturally DARPA gathered a panel of experts to discuss one of life's greatest questions: are we alone in the universe?

The panelists stated that in spite of the Fermi paradox, there are several reasons not to be discouraged that we haven't found alien life yet. According to Lucianne Walkowicz, an astronomer who works on the Kepler Space Telescope, we haven't even really begun the search yet:

"We haven't really looked," she said. "Astrobiology is a wonderful hot new thing in astronomy, but to say that you're looking for intelligent life in the universe is still actually a pretty fringe-y thing to do. We have this image that we've been listening for radio signals, that we've been searching for life in the universe, but actually we've been resource poor in that area."

Listening for radio signals from other technologically advanced civilizations has been the predominant method for searching for alien life in recent years, but not only have we failed to devote enough resources to this effort, this method could be based on completely erroneous assumptions, according to Walkowicz. Our species has only been sending radio waves into the universe for a historically short period of time, and our radio activity is getting quieter as we become more advanced. There's a possibility that an extremely advanced civilization would have progressed beyond radio waves, or would have bypassed that stage altogether.

Thinking outside the box even more, there's no reason to think that the aliens would be anything like humans at all. If they were dolphin-like intelligent mammals, they may never have ventured outside of the water, in which case they wouldn't be using radio signals. Furthermore, they wouldn't necessarily be able to see the stars, which would make it much less likely that they would become curious about species living on other planets. This is one of many similar explanations that could resolve the Fermi paradox, according to the panelists.

"There is a lot of leeway to understand what kinds of life may be out there, and what other biosignatures might we be looking for," she said. "Pressing that frontier forward, understanding what other signatures might be out there, is something we could potentially do experimentally."

According to Walkowicz, if there is (or ever was) extraterrestrial life in our solar system, it likely exists on Mars. If we definitively prove that it is lifeless, we may be tempted to immediately terraform and inhabit it, but Walkowicz insists that this would be a mistake, as it might destroy evidence of an independent origin of life on another planet besides Earth, even if those species are long gone.

"The way we should default to thinking about Mars is thinking about it as a nature preserve," she said in the panel (via Popular Science). "It is our most reachable target for understanding the possible independent origin of life, or the independent evolution of life. ...If we were to go to Mars and terraform it, we lose the ability to answer the question of whether there is an independent origin of life."

This relates to a common concern in the search for alien life: if habitable planets undergo cycles of life and lifelessness, then Earth might simply be in a different stage of the cycle, and we could be the only extant intelligent species in the universe for the brief period of time that we exist. Mark Norell, a paleontologist at the American Museum of Natural History, assured the audience that even if certain extraterrestrial species were wiped out, we would likely find other species, or at least evidence that they once existed:

"The one thing replicating DNA seems to have in common on this planet is it is very resilient. The rebound has been fast," he said. "You would be pretty hard-pressed to go to a place on another planet and only find fossil life, and find everything on the entire planet totally exterminated."

In conclusion, Geoff Ling of DARPA said this line of thinking was consistent with the agency's mandate: "To go and think of things that others really don't."

"You won't find unless you explore," he said. "Biology is a very rich discipline, and is a place where, I would argue, surprise is waiting for us. If somebody is going to do it, let it be DARPA."